Field of the Disclosure
The present disclosure relates to a flexible display device.
Discussion of the Related Art
Recently, a flexible display device has been suggested which uses a resin substrate having flexibility rather than a glass substrate which has been widely used for a display device such as a liquid crystal display device or an EL display device. An antireflective film having an antireflective layer (low refractive index layer) is disposed on an image display surface of the display device to prevent an external light such as a fluorescent tube from being reflected and to improve visibility. The antireflective layer needs flex resistance as well as high antireflection and transparency.
To fabricate an antireflective film, the following technologies have been known: a technology of forming a low refractive index layer of a silica film on a surface of a film by a plasma CVD method (referred to as “Patent document 1” of Japanese Patent Publication No. 2004-258394, for example); and a technology of forming a low refractive index layer by using forming an adjacent layer including silicone oil or silicone surfactant on a film, applying and drying a coating solution including a low refractive index material on the adjacent layer, and then curing the coating solution (referred to as “Patent document 2” of Japanese Patent Publication No. 2005-338549).
However, in the technology of the Patent document 1, there is a problem that initial costs increase and productivity is low because plasma CVD equipment needs to be newly introduced to form the low refractive index layer of silica film. Moreover, in the Patent document 1, although it is disclosed that a hard coating layer of thermosetting resin or inonizing radiation-curable resin can be formed between the film and the low refractive index layer, when the hard coating layer is formed, there is another problem that scratch resistance increases but folding endurance is considerably lowered. Meanwhile, in the technology of the Patent document 2, since a process of forming a plurality of layers is necessary, there are problems that the productivity is low, costs are raised, and the transparency of the obtained antireflective film is not enough. As stated above, the antireflective film according to the related art is not satisfactory for the flexible display device.